A revised key to the subfamilies, tribes and subtribes of the Cetoniidae (Coleoptera: Scarabaeoidea) is presented. Comments are given on the classification implied by the key, which includes several redefinitions. All the known genera (ca. 510) are listed under their tribe or subtribe, the position of several being different from that in Schenkling's catalogues (1921, 1922). References to recent synoptic literature are given. Eighteen new subtribes are proposed, the majority in the tribe Cremastocheilini. One new tribe is proposed, the Platygeniini. Attention is drawn to various new and neglected synonymies, original spellings, and other nomenclatural matters regarding family-group and genus-group names. The position of many genera is briefly discussed.Some striking features of the biogeography of the Cetoniidae are discussed, such as the high generic endemicity for the major biogeographical regions (for the Madagascan, Afrotropical and Australasian regions ca. 90% or more).